The seismic record is the recorded result of the seismic wavelet, which is produced by the hypocenter, recorded after the seismic wavelet spreads to the underground and is reflected back to the ground when met by the reflecting boundary. The vertical seismic resolution depends on the dominant frequency of the seismic wavelet, which is affected by the excited condition and spread condition. When the hypocenter of the seismic dynamite is generated, the wave dispersion of the seismic wavelet is improved by the amount of the dynamite or loosed by the stratum at the point of the detonation, therefore the dominant frequency of the seismic wavelet will be lowered. The attenuation, such as absorption, scattering, etc. takes place during the spreading process of the seismic wavelet. The seismic wavelet continues to improve with distortion. In particular, when the seismic wavelet is spreading at the near-surface, the attenuation and the wave dispersion of the seismic wavelet are relatively large. The amount of the attenuation each meter of the near-surface is relatively 500-1000 times higher than that of the high-velocity layer. The attenuation of the seismic wave is different due to the difference of the altitude of the near-surface and the lithology of the stratum.
it is effective to improve the vertical seismic resolution using processing technology, such as the field acquisition of the present high resolution and the static correction, spectra albino, wavelet de-convolution, anti-Q filtering, and the like. However, the apparent dominant frequency cannot be sufficient for the need of recognizing the thin layer in the present seismic exploration, since it can only be improved to around 60 Hz.